Robotic wheel gripper with a TPM sensor

ABSTRACT

A robotic wheel gripper unit that is configured for gripping and transporting a wheel to a predetermined position during an assembly operation with a tire is disclosed. The robotic wheel gripper unit comprises a selectively moveable arm that includes a gripper tool connected thereto. The gripper tool further includes a plurality of gripper fingers and at least one sensor. The gripper fingers are configured for selectively engaging a portion of a wheel. The sensor is configured to detect a predetermined element on the wheel, such as a TPMS valve stem, to assist in placement of the wheel during an assembly operation.

CROSS-REFERENCE TO RELATED APPLICATION

This application is the U.S. national phase of PCT Application No.PCT/US2015/038575 filed on Jun. 30, 2015, which claims the benefit ofU.S. Provisional Application Ser. No. 62/019,536 filed on Jul. 1, 2014,the disclosures of which are incorporated in their entirety by referenceherein.

TECHNICAL FIELD

The present disclosure relates to a robotic wheel gripper. Morespecifically, the present disclosure relates to a robotic wheel gripperthat is configured to orient/rotate the wheel to position a tirepressure monitor sensor (“TPMS”) valve stem in a predetermined positionto prevent damage to the TPMS valve stem during an assembly operationwhere the tire is mounted to the wheel.

BACKGROUND

In one exemplary automated tire/wheel assembly system, wheels aretransported via a first conveyor system, while the tires are deliveredvia a second conveyor system. An assembly conveyor is positioned betweenthe first and second conveyor systems. A wheel load robot is configuredto grip a wheel and move it to an assembly conveyor, while a tire loadrobot grips a tire and moves it to the assembly conveyor, so as topartially position the tire on the wheel at an angle to create atire/wheel subassembly. The tire/wheel subassembly is then transportedby the assembly conveyor to a mounting robot. The tire is then mountedon the wheel by the mounting robot so as to fully seat the tire on thewheel, prior to inflation of the tire.

However, one issue that remains problematic in such an automatedassembly is that current wheels include valve stem TPM sensors that needto be positioned at a certain angle to properly mate with the tire,without damage the TPM sensors during the assembly operation. Indeed,the degree of precision required in locating the TPM valve stem sensorduring assembly of the wheel/tire assembly is problematic becausethreads of the TPM valve stem can be irreparably damaged duringassembly. Accordingly, what is needed is a system that can locate theTPM valve stem and position the wheel on the assembly conveyor so as toproperly place the wheel on the tire before the wheel is fully seated soas to prevent damage to the TPM valve stem.

SUMMARY

A robotic wheel gripper unit that is configured for gripping andtransporting a wheel to a predetermined position during an assemblyoperation with a tire is disclosed. In one exemplary arrangement, therobotic wheel gripper unit comprises a selectively moveable arm thatincludes a gripper tool connected thereto. The gripper tool furtherincludes a plurality of gripper fingers and at least one sensor. Thegripper fingers are configured for selectively engaging a portion of awheel. The sensor is configured to detect a predetermined element on thewheel, such as a TPMS valve stem, to assist in placement of the wheel ata predetermined position during an assembly operation to prevent damageof the wheel element during an assembly operation of mounting a tire tothe wheel.

In one exemplary arrangement, the gripper fingers are carried onplatforms that are selectively moveable from a releasing position to agripping position. When the gripper fingers are in the releasingposition, the gripper fingers are moved laterally away from the wheel.The gripper fingers may include grooves that are configured to engagewith the portion of the wheel when the gripper fingers are in thegripping position.

In one exemplary arrangement, the gripper tool includes two pairs ofgripper fingers, with each pair being carried on a common platform. Thesensor may be mounted to one of the platforms. For example, in onearrangement, the sensor is mounted to a sensor plate that extends fromone of the platforms that carry the gripper fingers.

In one exemplary arrangement the sensor is an optical sensor. The sensoris operatively connected to a controller that records the position ofthe tire pressure monitor system valve stem with respect to a fixedposition such that the gripper tool may position the wheel on anassembly conveyor in a predetermined position to locate the tirepressure monitor system valve stem at a predetermined orientation duringan assembly operation with a tire.

A method of operating a robotic wheel gripper unit is also disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a robotic wheel gripper in an initialposition;

FIG. 2 is a front elevational view of the robotic wheel gripper of FIG.1 in the initial position;

FIG. 3 is a front elevational view of the robotic wheel gripper of FIG.1 in a scan position;

FIG. 4 is a first side elevational view of the robotic wheel gripper ofFIG. 1 in the scan position, as an end effector rotates around thewheel;

FIG. 5 is a second side elevational view of the robotic wheel gripper ofFIG. 1, in the scan position, as the end effector rotates around thewheel;

FIG. 6 is a top plan view of the robotic wheel gripper of FIG. 1, in thescan position, as the end effector rotates around the wheel;

FIG. 7 is a front elevational view of the robotic wheel gripper of FIG.1, in a gripping position;

FIG. 8 is a first side elevational view of the robotic wheel gripper ofFIG. 1, in the gripping position;

FIG. 9 is a second side elevational view of the robotic wheel gripper ofFIG. 1, in the gripping position;

FIG. 10 is a front elevational view of the robotic wheel gripper of FIG.1, as the robotic wheel gripper releases the wheel;

FIG. 11 is a perspective view of the robotic wheel gripper of FIG. 1,when the robotic wheel gripper retracts from the wheel; and

FIG. 12 is a flow chart illustrating the operation of the robotic wheelgripper.

DETAILED DESCRIPTION

As required, detailed embodiments of the present invention are disclosedherein; however, it is to be understood that the disclosed embodimentsare merely exemplary of the invention that may be embodied in variousand alternative forms. The figures are not necessarily to scale; somefeatures may be exaggerated or minimized to show details of particularcomponents. Therefore, specific structural and functional detailsdisclosed herein are not to be interpreted as limiting, but merely as arepresentative basis for teaching one skilled in the art to variouslyemploy the present invention.

Referring to FIGS. 1-12, a robotic wheel gripper 10 that is configuredfor gripping a wheel 12 so as to properly load the wheel 12 on anassembly conveyor is disclosed. The robotic wheel gripper 10 is operablesuch that a TPMS valve stem 14 may be oriented at a predeterminedposition during assembly with a tire during the assembly process. Inthis manner, the TPMS valve stem 14 will not be damaged when the tire isassembled to the wheel 12. The robotic wheel gripper 10 may include atleast one articulated joint 16 and a wrist 18. An arm 19 is positionedbetween the joint 16 and the wrist 18. The robotic wheel gripper 10 iscapable of movement with at least three degrees of freedom along one ofa selectable plurality of programmable predetermined paths. A grippertool 20 is mounted to the wrist 18 of the robotic wheel gripper 10.

The joint 16 is mounted to a body portion 22 that is connected to a baseportion 24. In one exemplary arrangement, the body portion 22 isrotatably-connected to the base portion 24 such that the body portion 22may be pivoted relative to the base portion 24. Further, the bodyportion 22 may be hinged to the base portion such that the body portion22 may be articulated vertically relative to the base portion 24.

In one exemplary embodiment, the arm 19 may be connected to the bodyportion 22 such that the arm 19 may be articulated in any desirableupward or downward position relative the body portion 22. Similar to therotatable connection of the base portion 24 and body portion 22, thegripper tool 20 may be rotatably-connected to the arm 19 such that thegripper tool 20 may be rotated, pivoted or otherwise spun 360° relativethe arm 19; as will be described in further detail below.

The gripper tool 20 includes a plurality of gripper fingers 26. Eachgripper finger 26 further comprises a grip groove 28 that is configuredfor selectively engaging an upper flange 30 of the wheel 12 (best seenin FIGS. 2-3). In one exemplary arrangement, the gripper tool 20includes 4 gripper fingers 26, with the gripper fingers 26 arranged inopposing pairs. The gripper tool 20 also comprises at least one sensor31 that is configured to locate the TPMS valve stem 14. In one exemplaryarrangement, the sensor 31 is an optical sensor such as an LED sensor.However, other sensors are contemplated.

The gripper fingers 26 may be carried on platforms 32 that areselectively moveable from a releasing position (i.e., FIG. 2) to agripping position (i.e., FIG. 8). In the releasing position, theopposing gripper fingers 26 are moved away from one another. In thegripping position, the opposing gripper fingers 26 are moved toward oneanother, to a distance that is approximately the width of the wheel 12.The sensor 31 may be mounted on a separate sensor plate 34 that isconnected to one of the platforms 32, so as to be positioned between oneof the pairs of the gripper fingers 26. With this configuration, thesensor 31 will move with the gripper fingers 26.

The operation of the robotic wheel gripper 10 will not be described inconnection with the flow chart in FIG. 12, as well as FIGS. 1-11. Morespecifically, in an initial step 100, the wheel 12 is initiallypositioned on wheel conveyor system (not shown) or platform (not shown)in a known, conventional manner. The robotic wheel gripper 10 has thearm 19 that is carrying the gripper tool 20 fully raised such that abottom surface 35 of the gripper fingers 26 is positioned above the topflange 30 of the wheel 12. The gripper tool 20 is positioned, however,directly over the wheel 12 so as to be centered over the wheel 12, asshown in FIG. 2, for example.

In step 102, the gripper tool 20 is moved downward over the wheel 12into a scanning position. More specifically, as may be seen in FIG. 3,the arm 19 is pivoted such that the gripper tool 20 is lowered. In thescanning position, the gripper fingers 26 are positioned to straddlearound the wheel 12. In other words, the bottom surface 35 of thegripper fingers 26 are positioned below the top flange 30 of the wheel12. The sensor 31 is also positioned below the top flange 30, but isconfigured to be located in the plane where the TPMS valve stem 14 ispositioned on the wheel 12, such that a beam 38 from the sensor 31 willintersect the TPMS valve stem 14 during the scanning operation. In oneexemplary configuration, the robot 10 can be programmed to lower to acertain predetermined height to ensure that the sensor 31 intersectswith the TPMS valve stem 14. In step 102, the gripper fingers 26 arestill in a releasing position, such that the gripper fingers 26 are notcontacting the wheel 12.

Referring to FIGS. 4-6, once in the scanning position, in step 104, thegripper tool 20 is then operated to rotate around the wheel 12. Morespecifically, the gripper tool 20 rotates around the wheel 12 (asillustrated by arrows A in FIG. 6) until a beam 38 of light from thesensor 31 intersects the TPMS valve stem 14 so as to locate the TPMSvalve stem 14. Once the TPMS valve stem 14 is located, the process moveson to step 106.

In step 106, the robotic wheel gripper 10 records the angle where theTPMS valve stem 14 is located relative to a fixed reference point. Theprocess then proceeds to step 108.

Referring to FIGS. 7-8, in step 108, the gripper tool 20 is refractedupwardly (with respect to the wheel 12) a predetermined distance so asto align the grip grooves 28 of the gripper fingers 26 with the upperflange 30 of the wheel 12. Once positioned, the gripper fingers 26 aremoved into an engagement position. More specifically, the gripperfingers 26 are moved inwardly and into contact with the upper flange 30of the wheel 12. The process then proceeds to step 110.

In step 110, referring to FIG. 9, the robotic wheel gripper 10 willrotate the wheel 12 and move the wheel 12 to orient the TPMS valve stem14 to a predetermined position such that assembly to the tire will notlead to damage. In one exemplary arrangement, the robotic wheel gripper10 rotates the wheel 12 while simultaneously moving the wheel 12 to theassembly conveyor. The process then proceeds to step 112.

In step 112, and referring specifically to FIG. 10, once the wheel 12 ispositioned on the assembly conveyor (not shown), with the TPMS valvestem 14 oriented to a predetermined position, the gripper tool 20 movesinto the releasing position. More specifically, the gripper fingers 26are moved away from the wheel 12, so as to release the wheel from thegripper tool 20. Next, referring to FIG. 11, the arm 19 is retracted soas to lift the gripper tool 20 upward and away from wheel 12. Once thearm 19 is retracted, the robotic wheel gripper 10 will return to thewheel conveyor (not shown) and is positioned over another wheel 12 tobegin the process again.

It is understood that the robotic wheel gripper 10 may be automaticallyoperated by a controller (not shown) that is configured to lift and movewheel 12 at predetermined time intervals, including coordinating withother robots to producing an automated wheel/tire assembly and inflationsystem.

While exemplary embodiments are described above, it is not intended thatthese embodiments describe all possible forms of the invention. Rather,the words used in the specification are words of description rather thanlimitation, and it is understood that various changes may be madewithout departing from the spirit and scope of the invention.Additionally, the features of various implementing embodiments may becombined to form further embodiments of the invention.

What is claimed is:
 1. A robotic wheel gripper unit configured forgripping and transporting a wheel to a predetermined position;comprising: a selectively moveable arm; and a gripper tool that isconnected to a first end of the moveable arm; wherein the gripper toolfurther comprises a plurality of gripper fingers carried on platformsand configured for selectively engaging a portion of a wheel; andwherein the gripper tool further comprises at least one sensor mountedto at least one of the platforms and configured to detect a location ofa predetermined element on the wheel, wherein the sensor is configuredto locate a tire pressure monitor system valve stem on the wheel andfurther wherein the sensor is operatively connected to a controller thatrecords the position of the tire pressure monitor system valve stem withrespect to a fixed position such that the gripper tool may position thewheel on an assembly conveyor in a predetermined position to locate thetire pressure monitor system valve stem at a predetermined orientationduring an assembly operation with a tire.
 2. The robotic wheel gripperunit of claim 1, wherein the gripper fingers are selectively moveablefrom a releasing position to a gripping position, wherein in thereleasing position, the gripper fingers are moved laterally away fromthe wheel.
 3. The robotic wheel gripper unit of claim 2, wherein thegripper fingers further comprise gripper grooves that are configured toengage with the portion of the wheel when the gripper fingers are in thegripping position.
 4. The robotic wheel gripper unit of claim 2, wherethe gripper tool includes two pairs of gripper fingers, with each pairbeing carried on a common platform.
 5. The robotic wheel gripper unit ofclaim 1, wherein the sensor is mounted to a sensor plate that extendsfrom one of the platforms.
 6. The robotic wheel gripper unit of claim 1,wherein the sensor is an optical sensor.
 7. The robotic wheel gripperunit of claim 1, wherein the moveable arm is operatively connected at asecond end thereof to a body portion, wherein the body portion isrotatably-connected to a base portion such that the base portion may bepivoted relative to the base portion.
 8. A robotic wheel gripper unitconfigured for gripping and transporting a wheel to a predeterminedposition; comprising: a selectively moveable arm; and a gripper toolconnected to a first end of the moveable arm and having two pairs ofgripper fingers, each pair carried on one of a pair of platforms andconfigured to selectively engage a portion of a wheel, wherein thegripper tool further comprises at least one sensor mounted to at leastone of the platforms and is configured to detect a location of apredetermined element on the wheel, wherein the sensor is configured tolocate a tire pressure monitor system valve stem on the wheel andfurther wherein the sensor is operatively connected to a controller thatrecords the position of the tire pressure monitor system valve stem withrespect to a fixed position such that the gripper tool may position thewheel on an assembly conveyor in a predetermined position to locate thetire pressure monitor system valve stem at a predetermined orientationduring an assembly operation with a tire.